Valve assemblies are known that include modifications such that a predetermined tap rotational orientation can be recorded and that position can then be repeatedly selected by a user. U.S. Pat. No. 5,427,140 to the present applicant, John Bosanquet, describes such an assembly that makes use of both a mechanical recordal of position as well as a light-registering type position recordal configuration. However, the configurations of the prior art do not adequately address multiple user situations, nor do they take into account changes in supply fluid parameters (eg. variations in municipal water supply temperatures, flow rates etc).